Most of the following Starfleet standard probes were mentioned in various episodes. The
depictions and specifications are taken from the TNG Technical Manual,
whereas an identification on screen was usually not possible owing to their
small size relative to the starships. Possible inconsistencies in the appearance
and performance of probes may be easily explained in that there are frequent
upgrades, sometimes with new casings, in accordance with the DS9 Technical Manual.

Class 1

General
descriptionThis type of probes is equipped with a full EM/subspace and
interstellar chemistry pallet for in-space applications.

Known probesNo name given

Annotations1)
Probes of Class 1 were mentioned and shown in TNG: "Where Silence Has
Lease", "Time Squared", "Pen Pals" and
"The Defector". They were just mentioned in
"Reunion". In "Where Silence Has Lease" there was a model looking like the TNGTM depiction. In
"Pen Pals" it was just a light effect, but here it makes
sense considering that Worf mentioned they would use torpedo casings
for this particular mission. Finally, a display of the Mirror Defiant
in "Shattered Mirror" depicted the Class-1 or Class-2 probe
along with the Defiant MSD, hence confirming that probes looking like
this really exist.
2) The DS9TM states that the
Class 1 has an effective range of 32*106km and a total
delta-v of 0.6c. If this is true, it means a considerable upgrade
of the device.

General
descriptionThis type of probes is equipped with a full EM/subspace and
interstellar chemistry pallet for in-space applications. It is based
on Class 1. In addition, Class 2 has enhanced long-range particle and field
detectors and imaging system.Gallery: Other Small Federation
Vessels

Known probesNo name given

AnnotationsThis probe is visible
in
TNG: "The Most Toys", where is is just represented by a light.
Additionally, Class 2 is mentioned in DS9: "Battle Lines". A relatively detailed model of the probe, closely resembling
the design in the TNGTM, was built for VOY: "Real Life", although here it is once again only visible in the form
of some lights.

SpecificationsSensor probe
Range: 400,000km
Max. speed: 0.65c

Class 3

General
descriptionThis is a planetary probe, with a full range of terrestrial soft
landing to subsurface penetrator missions. Gas giant atmosphere
missions are survivable up to 450bar pressure.

Known probesNo name given

AnnotationsThis type shows up in TNG: "The Enemy"
where is resembles rather Class 1 or 2 than the TNGTM
depiction of Class 3. The probe is also referred to in DS9: "Valiant".

SpecificationsPlanetary probe
Range: 1,200,000km
Max. speed: 0.65c

Class 4

General
descriptionThis is a stellar encounter probe, modified from Class 3. The probe
is equipped
with triply redundant stellar fields and particle detectors and a
stellar atmosphere analysis suite. There are six ejectable/survivable
radiation flux subprobes, deployable for nonstellar energy phenomena.

Known probesNo name given

Annotations1)
In DS9: "If Wishes Were Horses" such a probe is launched from Deep Space 9, but it looks quite different than the TNGTM
depiction. Maybe this is already the upgrade mentioned in the DS9TM.
The same detailed model (it looks much like s small starship, even
with something looking like warp nacelles) is
visible in "Rejoined" where the probe is launched somewhere
from the Defiant's deflector. In addition, probes of this type are
mentioned in TNG: "Rascals", "Relics" and DS9: "Children of
Time". The Class-4 probe is used in TNG: "Relics" to study the
Dyson Sphere, although it doesn't seem to be the best-suited type.
2) The same model of Class 4 as in its previous appearances on DS9 is
also used in DS9: "Meridian", this time for a probe whose
designation is not mentioned but which is launched into a star's
corona. Since this is exactly the purpose of Class 4, we silently
assume it is another appearance of this very type.
3) According to the DS9TM,
the new effective range of Class 4 is 72.3*106km, and the
total delta-v is 0.98c.

General
descriptionThis is a medium-range reconnaissance probe, with extended passive
data-gathering and recording systems. The probe has a full autonomous
mission execution and return system and is capable of atmosphere entry
and soft landing. It is coated for low observability and may be
modified for tactical missions with a custom sensor countermeasure
package.

Known probesNo name given

Annotations
1) Such a probe is mentioned but not shown in TNG: "Chain of Command".2)
In VOY: "Blink of an Eye" B'Elanna modifies a Class-5
probe for low-orbit observation. Although the Class 5 is designed as a
mid-range warp probe, the special environment of the
"accelerated" planet may require its use (also because of
its low observability). The probe seen in the episode looks like
the multispatial probe (see below). This may be exactly the common new casing the DS9TM
mentions for the combined Class 4 and 5.3) The DS9TM notes that "the
class-4 and class-5 upgrades have been combined into a single new
class-5-type hull casing". The new effective range of Class 5
is 84.2*109km, and the total delta-v is Warp 2.6.

General
descriptionThis is a comm relay and emergency beacon, modified from Class 3. It
provides 9270 RF and subspace channels, with a 360° antenna coverage
and 0.0001 arc-second high-gain antenna pointing resolution. The probe
features an extended deuterium supply for transceiver power generation
and planetary orbit plane changes.

General
descriptionThis is a remote culture study probe, modified from Class 5. It is
applicable to civilizations up to level III and has low observability
coatings and hull materials. The maximum loiter time is 3.5 months. A
low-impact molecular destruct package is tied to antitamper
detectors.

General
descriptionThis probe uses a modified photon torpedo casing. It is equipped
with a standard sensor pallet and mission-specific modules. Its
applications vary from galactic particles and fields research to
early-warning reconnaissance missions.

Known probesNo name given

AnnotationsA modified
probe of this type was used for the transport of K'Ehleyr in TNG:
"The Emissary".

General
descriptionThis probe uses a modified photon torpedo casing. It is equipped
with a standard sensor pallet and mission-specific modules. The
typical application is an emergency log/message capsule on homing
trajectory to the nearest starbase or known Starfleet vessel position.

General
descriptionThis may be another standard probe, but further specifications are
unknown.

Known probesNo name given

AnnotationsWhen the Defiant was trapped inside a gas giant's atmosphere in DS9:
"Starship Down", this probe was modified and used to destroy
a Jem'Hadar attack ship. Maybe this is just Class 3 in a new casing?

General
descriptionThe interface probe is a remote-controlled device for investigations
is hostile environmental conditions.

Known probesNo name given

AnnotationsThe
probe appeared in TNG: "Interface" where Geordi controlled
it through his neural interface. It may have been designed for indoor
use and hence not a space probe in a
classical sense, but could most likely be operated in open space as
well.

Annotations1)
The miniatures of the probes, seen in TNG: "Best of Both Worlds", are made
from a Soviet Typhoon-class submarine, with two Los Angeles-class
submarines as nacelles.
2) It is uncertain whether these probes are capable of Warp flight. It
seems they are sublight probes, since they approached the Borg cube as
late as it had already crossed the Mars perimeter.
3) The studio miniature also appeared in the Qualor II junkyard in
TNG: "Unification".

Specifications
None available

Microprobe

General
descriptionMicroprobes belong to the inventory of USS Voyager.

Known probesNo name given

Annotations
Microprobes were mentioned in VOY: "The Cloud" and "Eye
of the Needle", represented just by a light effect.

AnnotationsThe multispatial probe must be something immensely valuable, as the
crew took all the efforts and the danger to build the Delta Flyer and
enter a gas giant atmosphere, only to retrieve this probe in VOY:
"Extreme Risk". Its purpose, however, remains a mystery.

AnnotationsVoyager launched such a beacon while in "chaotic space" in
VOY: "The Fight", where it served as a navigation aid. It is
possible that this probe is a further development of the above Class
6.

AnnotationsThe soliton wave test took place (and failed) in TNG: "New
Ground". It makes sense that Starfleet would use an existing
large probe resembling a starship for this purpose. It was not
mentioned in the episode that the probe was specifically built for the
test, so it could be the same type as the Mars perimeter defense
probes whose miniature was re-used here.

Specifications
None available

Ultraviolet
satellite

General
descriptionThe only purpose of these small satellites is to emit ultraviolet
radiation. They can be deployed from 23rd century Federation starships
in a planet's orbit and are energized via remote control.

Known satellitesNo name given

AnnotationsWe
can see the satellites for the first time in the TOS-R version of
"Operation: Annihilate!". It remains unknown whether the no
less than 210 deployed satellites were specially constructed to fight
the neural parasite infestation on Deneva. Most likely the basic
satellites were ready-made standard devices with power supply, radio
receivers and attitude control. But they needed to be rigged at least
with the ultraviolet emitters that don't sound like they could be
available on standard-issue satellites or buoys. A lot of work for
Scotty and his staff!

Specifications
None available

Uncertain
Probes

It is uncertain whether the
following probes whose name or purpose was not explicitly stated exist as
distinct types. Maybe they just belong to one of the above standard
types, even if they look somewhat different.

Emergency buoy

General
descriptionThis type of buoys can be launched from Galaxy-class ships to
transmit the log entries.

Known buoysNo name given

AnnotationsThe
buoy appeared in TNG: "Descent". Its purpose sounds very
much like the one of the above standard probe Class 6.

Specifications
None available

Scanner probe

General
descriptionIt is unknown whether this could be one of the standard probes.

Known probesNo name given

AnnotationsBefore
the standard probe of Class 1 is started in
TNG: "Where Silence Has Lease", Picard orders the launch of
a "scanner probe" that vanishes after a few seconds. The
scanner probe is likely a device with fewer options and a smaller
range than Class 1. On the other hand, Class 1 is already the least
complex of the standard probes. The footage is identical to the later
Class 1 probe in the same episode "Where Silence Has Lease".
The probe would later appear as Class 3 in TNG:
"The Enemy".

Specifications
None available

Uncertain probe 1

General
descriptionIt is unknown whether this is a distinct type of probes and what
purpose it is used for.

Known probesNo name given

AnnotationsA not further specified probe was launched in TNG:
"The Outcast". While it resembled the standard types in the TNGTM,
there is no perfect match. At least, it appears to be new footage.

Specifications
None available

Uncertain probe 2

General
descriptionIt is unknown whether this is a distinct type of probes and what
purpose it is used for.

Known probesNo name given

AnnotationsA
not further specified probe was launched in TNG: "Lower
Decks". It resembled the standard types in (Class 1 and 2 in the TNGTM,
Class 1 and 3 on screen). This probe was previously seen as emergency
buoy in TNG: "Descent" (see above).

Specifications
None available

Unknown
Probes

Quadros 1,
long-range probe, launched in the 22nd century, explored parts of the Gamma
Quadrant, including the Idran system (DS9: "Emissary")

Vega IX,
long-range probe that was sent to record the collapse
of the star Beta Stromgren and discovered the living
ship named Gomtuu (TNG: "Tin Man") We
may assume that Vega IX is the individual name of the probe.